…mentations.

- Add multiple new test files with neural network examples and testing code
- Implement techniques such as multi-layer networks, convolutional layers, regularization, and deep networks
- Improve code readability and formatting with docstrings, white space, and f-strings
- Modify test files to load and preprocess MNIST data for use in neural networks
- Update imports and remove unnecessary code to optimize testing speed

- Add feedforward neural network implementation with backpropagation in `my_network1.py`
- Include `Network` class with initialization, feed forward, stochastic gradient descent, mini batch update, backpropagation, and evaluation methods
- Import `my_network1`, `numpy`, and `mnist_loader` in `test_network1.py`
- Create new testing file `test_network1.py`
- Include comments explaining code and usage of certain parameters
- Define `sigmoid` and `sigmoid_prime` functions for activation and derivative calculation
- Add `%load network.py` to the beginning of `network.py`